Package structure, packaging method and electronic device

ABSTRACT

The beneficial effects of the present application are as follows: the modified epoxy resin is doped with the modified epoxy resin in the buffer layer, the modified epoxy resin is reacted with the first barrier layer under UV irradiation, so that the modified epoxy resin is adhered to the first barrier layer to adhere the buffer layer and the first barrier layer and solve the technical problem that the organic layer and the inorganic layer are easily peeled off in the prior art. The present application also provides a packaging method and an electronic device.

RELATED APPLICATIONS

This application is a continuation application of PCT Patent ApplicationNo. PCT/CN2018/073840, filed Jan. 23, 2018, which claims the prioritybenefit of Chinese Patent Application No. CN 201711103046.6, filed Nov.10, 2017, which is herein incorporated by reference in its entirety.

FIELD OF THE DISCLOSURE

The present disclosure relates to an OLED technology field, and moreparticularly to a package structure, a packaging method and anelectronic device.

BACKGROUND OF THE DISCLOSURE

OLED is very sensitive to water and oxygen, in order to achieve a goodwater blocking oxygen effect, the commonly used thin film encapsulationof its water blocking oxygen performance requirements. Inorganic thinfilm layer of water resistance oxygen capacity is generally much betterthan the organic thin film layer, but in the application of flexibleproducts, the inorganic thin film layer of stress in the flexiblebending process and its prone to fracture phenomenon. Therefore, theorganic thin film layer is often used as a buffer layer in order toachieve the purpose of releasing the stress of the inorganic film layerand enhancing the flexibility of the thin film encapsulation material.However, the performance of the organic/inorganic thin film layers isgreatly different from each other, and the phenomenon that the filmlayers are peeled off each other often occurs.

SUMMARY OF THE DISCLOSURE

The purpose of the present application is to provide a package structureto solve the problem that the prior art has the problem that the filmlayers are peeled off each other.

For the purpose of the present application, the present applicationprovides the following technical solutions.

In a first aspect, the present application provides a package structure,including a first barrier layer and a buffer layer arranged instacked-layers. The buffer layer is doped with a modified epoxy resin,and the modified epoxy resin is reactive with the first barrier layerunder UV irradiation configured to adhere the buffer layer to the firstbarrier layer.

In a first possible implementation manner of the first aspect, thebuffer layer includes a first surface in contact with the first barrierlayer and a second surface opposite to the first surface, theconcentration of the modified epoxy resin gradually decreases in adirection of the first surface toward the second surface.

With reference to the first aspect and the first possible implementationmanner of the first aspect, in a second possible implementation mannerof the first aspect, the modified epoxy resin is a modified epoxyacrylate, the modified epoxy acrylate has a chemical formula of

where at least one of the groups R1, R2, R3 or R4 has an alkoxy group.

With reference to the first aspect and the second possibleimplementation manner of the first aspect, in a third possibleimplementation manner of the first aspect, the surface of the firstbarrier layer further has a hydroxyl group, the chemical reactionequation of the hydroxyl group and the modified epoxy resin is:

In a fourth possible implementation manner of the first aspect, thefirst barrier layer includes a third surface in contact with the bufferlayer and a fourth surface opposite to the third surface, a groove isprovided in a middle of the fourth surface; the package structurefurther includes a substrate, a base layer and an inorganic film layerarranged in stacked-layers, the inorganic film layer and the firstbarrier layer are stacked, the fourth surface is in contact with theinorganic film layer, the groove and the inorganic film layer enclose toform a vacuum closed space, where the vacuum closed space is configuredto encapsulate the OLED layer.

With reference to the first aspect and the fourth possibleimplementation manner of the first aspect, in a fifth possibleimplementation manner of the first aspect, the package structure furtherincludes a second barrier layer, and the second barrier layer is stackedon the buffer layer.

With reference to the first aspect and the fifth possible implementationmanner of the first aspect, in a sixth possible implementation manner ofthe first aspect, the second barrier layer surrounds the first barrierlayer and a lateral surface of the buffer layer so that the OLED layeris surrounded by the first barrier layer and the second barrier layer.

With reference to the first aspect and the fifth possible implementationmanner of the first aspect, in a seventh possible implementation mannerof the first aspect, the buffer layer surrounds the first barrier layerand the second barrier layer surrounds the buffer layer such that theOLED layer is surrounded by the first barrier layer, the buffer layer,and the second barrier layer.

In a second aspect, the present application provides a packaging method,including the following steps:

-   providing a substrate, sequentially forming a base layer, an    inorganic film layer, an OLED layer and a first barrier layer on the    substrate;-   forming a buffer layer on the first barrier layer by using the    inkjet printing process, wherein the buffer layer is doped with a    modified epoxy acrylate;-   irradiating the buffer layer and the first barrier layer with UV    light so that the modified epoxy acrylate reacts with the first    barrier layer to adhere the buffer layer to the first barrier layer.

In a first possible implementation manner of the second aspect, thebuffer layer includes a first surface in contact with the first barrierlayer and a second surface opposite to the first surface, in fabricatingthe buffer layer, the ink jet printing process is used for a pluralityof times so that a basic layer is formed each time, the modified epoxyacrylate doped during ink jet printing is sequentially reduced so thatthe concentration of the modified epoxy acrylate in the buffer layergradually decreases in a direction of the first surface toward thesecond surface.

In a third aspect, the present application provides an electronicdevice, including the package structure in various implementations ofthe first aspect.

Beneficial effects of the present application:

in the package structure provided by the present application, themodified epoxy resin is doped in the buffer layer, the modified epoxyresin reacts with the first barrier layer under UV irradiation such thatthe modified epoxy resin is adhered to the first barrier layer foradhering the buffer layer and the first barrier layer, which solves thetechnical problem that the organic layer and the inorganic layer areeasily peeled off in the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS

To describe the technical solutions in the embodiments of the presentapplication or in the prior art more clearly, the following brieflyintroduces the accompanying drawings required for describing theembodiments or the prior art. Apparently, the accompanying drawings inthe following description show merely some embodiments of theapplication, and a person of ordinary skill in the art may still deriveother drawings from these accompanying drawings without creativeefforts.

FIG. 1 is a schematic structural diagram of the package structureaccording to the embodiment of the present application.

FIG. 2 is a schematic structural diagram of the buffer layer in FIG. 1macro structure.

FIG. 3 is a schematic structural diagram of the buffer layer in FIG. 2microstructure.

FIG. 4 is a schematic structural diagram of the package structure ofanother embodiment of FIG. 1.

FIG. 5 is a schematic structural diagram of the package structure ofanother embodiment of FIG. 1.

FIG. 6 is a schematic structural diagram of the package structure ofanother embodiment in FIG. 1.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The technical solutions in the embodiments of the present applicationare clearly and completely described below with reference to theaccompanying drawings in the embodiments of the present application.Apparently, the described embodiments are merely some but not all of theembodiments of the present application. All other embodiments obtainedby a person of ordinary skill in the art based on the embodiments of thepresent application without creative efforts shall fall in theprotection scope of this application.

Referring to FIG. 1, the embodiment of the present application providesa package structure, the package structure includes a first barrierlayer 51 and a buffer layer 52 stacked in layers, wherein the bufferlayer 52 is doped with a modified epoxy resin, the modified epoxy resincan react with the first barrier layer 51 under UV irradiation so as tomake the modified epoxy resin adhere to the first barrier layer 51 foradhering the buffer layer 52 and the first barrier layer 51.

In this embodiment, the modified epoxy resin is a modified epoxyacrylate, and the modified epoxy acrylate is formed by introducing analkoxy group into a common epoxy acrylate. Ordinary epoxy acrylates areobtained by the esterification of epoxy compounds with (meth) acrylicacid or with —OH. The commonly used epoxy compounds or epoxy resins arebisphenol A epoxy resin, hexahydrophthalic acid epoxy resin, aliphaticepoxy resin and the like. They are characterized by the p-position ofthe acrylic group has a —OH group, the molecule contains hydroxyl,ether, ester and other polar groups, so that resin molecules andadherend molecules have a strong interaction force, excellent adhesiveproperties. However, the traditional high viscosity epoxy acrylate (>500cps). It has been tested that modified epoxy acrylates can be preparedby introducing alkoxy groups into the molecular structure of epoxyacrylate, which can be much lower in viscosity (<20 cps) withoutaffecting their adhesive properties.

The ink doped with the modified epoxy acrylate is sprayed on the bufferlayer 52 in the package structure by ink jet printing (IJP) by doping acertain amount of the modified epoxy acrylate with ink. After the inkjetprinting process of UV curing, both to cure the ink, but also to curethe ink doped with modified epoxy acrylate, making the modified epoxyacrylate into excellent performance of UV curing glue, can play the roleof adhering the inorganic layer and the organic layer. In thisembodiment, the buffer layer 52 is an inorganic film layer, and thesurface of the buffer layer 52 usually contains a hydroxyl group (—OH).The modified epoxy acrylate contains an epoxy group, and the followingreaction can occur under ultraviolet light irradiation:

Where Inorganic-OH represents the first barrier layer, which has ahydroxyl group-OH; at least one of the groups R1, R2, R3 or R4 has analkoxy group, and other groups may contain a hydroxyl group, an ethergroup, an ester group and other polar groups.

Through the above reaction, a strong interaction force is formed betweenthe modified epoxy acrylate and the buffer layer 52, so that theproblems that the inorganic and organic film layers in the encapsulationstructure are easily peeled off can be effectively solved.

Of course, in other embodiments, the modified epoxy resin may also beother organic materials having epoxy groups as long as it has thefunction of adhering the organic layer and the inorganic layer.

In the present embodiment, due to the process of UV curing itself in theinkjet printing process, the process of doping the modified epoxy resincan directly use the UV curing process of the original inkjet printingwithout any additional process, thereby reducing the difficulty ofprocess manufacture.

In an implementation manner, referring to FIG. 1 to FIG. 3, the bufferlayer 52 includes a first surface S1 contacting with the first barrierlayer 51 and a second surface S2 facing away from the first surface S1.The modified epoxy resin is layered in the buffer layer 52, and theconcentration of the modified epoxy resin gradually decreases toward thesecond surface S2 along the first surface S1.

In this embodiment, please refer to FIG. 3, which is an enlargedmicroscopic view of the buffer layer 52. The layered buffer layer 52includes a first base layer 521, a second base layer 522, a third baselayer 523, an N^(th) base layer 52N. The concentration of each baselayer doped modified epoxy acrylate is gradually decreased to form amacrostructure of the buffer layer 52 as shown in FIG. 2 to enhance theadhesion effect of the buffer layer 52 and the first barrier layer 51,at the same time, it will not affect the ink's flattening effect.

In an implementation manner, referring to FIG. 1, the first barrierlayer 51 includes a third surface S3 in contact with the buffer layer 52and a fourth surface S4 opposite to the third surface S3. A groove 511is provided in the middle of the fourth surface S4. The packagestructure further includes a substrate 10, a basic layer 20 and aninorganic film layer 30 stacked on top of each other, the inorganic filmlayer 30 and the first barrier layer 51 are stacked, the fourth surfaceS4 is in contact with the inorganic film layer 30, the groove 511 andthe inorganic film layer 30 are enclosed to form a vacuum closed space,where the vacuum closed space is used to encapsulate the OLED layer.

In the present embodiment, the substrate 10 is preferably a glasssubstrate, the basic layer 20 is preferably a PI material, and theinorganic film layer 30 is a TFT layer. The fourth surface S4 of thefirst barrier layer 51 has a closed end 512 that is adhered to theinorganic film layer 30. The closed end 512 is located on both sides ofthe first barrier layer 51. The groove 511 is connected between the twoclosed ends 512 such that the space of the groove 511 enclosed by thetwo closed ends 512, the inorganic layer 30 and the first barrier layer512 is an enclosed space and is vacuum-treated for accommodating theOLED layer 40.

In an implementation manner, referring to FIG. 4, the package structurefurther includes a second barrier layer 53. The second barrier layer 53is stacked on the buffer layer 52 to further improve the water blockingcapacity of the package.

In this embodiment, specifically, the material of the second barrierlayer 53 may be the same as that of the first barrier layer 51, and bothof them are inorganic materials and have a good function of blockingwater and oxygen. Further, the concentration of the modified epoxyacrylate in the vicinity of the contact surface between the buffer layer52 and the second barrier layer 53 of the present embodiment isincreased so that the buffer layer 52 and the second barrier layer 53also have a good adhesion effect and are hard to peel off.

In an implementation manner, referring to FIG. 5, the second barrierlayer 53 surrounds the first barrier layer 51 and the buffer layer 52 sothat the OLED layer 40 is surrounded by the first barrier layer 51 andthe second barrier layer 53.

Specifically, the second barrier layer 53 includes a blocking end 531,the blocking end 531 includes two and is located at two opposite ends ofthe second blocking layer 53, the blocking ends 531 at both ends areadhered with the inorganic layer 30 so that the second barrier layer 53and the inorganic layer 30 are enclosed to form a cavity structure. TheOLED, the first barrier layer 52 and the buffer layer 52 areaccommodated in the cavity. By disposing the blocking end 531 of thesecond blocking layer 53, the side surfaces of the OLED layer areprotected by the first blocking layer 51 and the second blocking layer53, thereby improving the water blocking oxygen capability of thepackage.

In an implementation manner, referring to FIG. 6, the buffer layer 52surrounds the first barrier layer 51, the second barrier layer 53surrounds the buffer layer 52 such that the OLED layer is surrounded bythe first barrier layer 51, the buffer layer 52 and the second barrierlayer 53.

Specifically, the present embodiment is similar to the previousembodiment, except that the buffer layer 52 further includes a bufferend 520 provided at two opposite ends of the buffer layer 52, the bufferend 520 is adhered to the inorganic layer 30, the first barrier layer 51and the closed end 512 are surrounded by the buffer layer 52 and thebuffer end 520. The second barrier layer 53 and the barrier end 531surround the buffer layer 52 and the buffer end 520. By disposing thebuffer end 520 and the blocking end 531, the side surfaces of the OLEDlayer are protected by the first barrier layer 51, the buffer layer 52and the second barrier layer 53, thereby improving the water blockingoxygen capability of the package.

Referring to FIG. 1, an embodiment of the present application furtherprovides a packaging method, which includes the following steps:

-   providing a substrate 10, sequentially forming a base layer 20, an    inorganic film layer 30, an OLED layer 40 and a first barrier layer    51 on the substrate;-   forming a buffer layer 52 on the first barrier layer 51 by using the    inkjet printing process, wherein the buffer layer 52 is doped with a    modified epoxy acrylate;-   irradiating the buffer layer 52 and the first barrier layer 51 with    UV light so that the modified epoxy acrylate reacts with the first    barrier layer 51 to adhere the buffer layer 52 and the first barrier    layer 51.

In an implementation manner, referring to FIG. 1 to FIG. 3, the bufferlayer 52 includes a first surface in contact with the first barrierlayer 51 and a second surface opposite to the first surface. Infabricating the buffer layer 52, an ink-jet printing process is usedmultiple times to form a base layer 521/522/523/52N each time. Themodified epoxy acrylate doped during inkjet printing is sequentiallyreduced so that the concentration of the modified epoxy acrylate in thebuffer layer 52 is gradually decreased in a direction of the firstsurface toward the second surface.

An embodiment of the present application further provides an electronicdevice, which includes the package structure according to any one of thepreceding embodiments.

The above disclosure is only one preferred implementation of the presentapplication, and certainly can not be used to limit the scope of thepresent application. Those of ordinary skill in the art can understandthat all or part of the processes for implementing the foregoingembodiments and equivalent changes made according to the claims of thepresent application still fall within the scope of the application.

What is claimed is:
 1. A package structure, comprising a first barrierlayer and a buffer layer arranged in stacked-layers, wherein the bufferlayer is doped with a modified epoxy resin, and the modified epoxy resinis reactive with the first barrier layer under UV irradiation configuredto adhere the buffer layer to the first barrier layer; wherein thebuffer layer comprises a first surface in contact with the first barrierlayer and a second surface opposite to the first surface, aconcentration of the modified epoxy resin gradually decreases in adirection of the first surface toward the second surface.
 2. The packagestructure according to claim 1, wherein the modified epoxy resin is amodified epoxy acrylate, the modified epoxy acrylate has a chemicalformula of

where at least one of the groups R1, R2, R3 or R4 has an alkoxy group.3. The package structure according to claim 2, wherein a surface of thefirst barrier layer further has a hydroxyl group, a chemical reactionequation of the hydroxyl group and the modified epoxy resin is:


4. The package structure according to claim 1, wherein the first barrierlayer comprises a third surface in contact with the buffer layer and afourth surface opposite to the third surface, a groove is provided in amiddle of the fourth surface; the package structure further comprises asubstrate, a base layer and an inorganic film layer arranged instacked-layers, the inorganic film layer and the first barrier layer arestacked, the fourth surface is in contact with the inorganic film layer,the groove and the inorganic film layer enclose to form a vacuum closedspace, where the vacuum closed space is configured to encapsulate anOLED layer.
 5. The package structure according to claim 4, wherein thepackage structure further comprises a second barrier layer, and thesecond barrier layer is stacked on the buffer layer.
 6. The packagestructure according to claim 5, wherein the second barrier layersurrounds the first barrier layer and a lateral surface of the bufferlayer so that the OLED layer is surrounded by the first barrier layerand the second barrier layer.
 7. An electronic device, comprising afirst barrier layer and a buffer layer arranged in stacked-layers,wherein the buffer layer is doped with a modified epoxy resin, themodified epoxy resin is reactive with the first barrier layer under UVirradiation configured to adhere the buffer layer to the first barrierlayer; wherein the buffer layer comprises a first surface in contactwith the first barrier layer and a second surface opposite to the firstsurface, a concentration of the modified epoxy resin gradually decreasesin a direction of the first surface toward the second surface.
 8. Theelectronic device according to claim 7, wherein the modified epoxy resinis a modified epoxy acrylate, the modified epoxy acrylate has a chemicalformula of

where at least one of the groups R1, R2, R3 or R4 has an alkoxy group.9. The electronic device according to claim 8, wherein a surface of thefirst barrier layer further has a hydroxyl group, a chemical reactionequation of the hydroxyl group and the modified epoxy resin is:


10. The electronic device according to claim 7, wherein the firstbarrier layer comprises a third surface in contact with the buffer layerand a fourth surface opposite to the third surface, a groove is providedin a middle of the fourth surface; the electronic device furthercomprises a substrate, a base layer and an inorganic film layer arrangedin stacked-layers, the inorganic film layer and the first barrier layerare stacked, the fourth surface is in contact with the inorganic filmlayer, the groove and the inorganic film layer enclose to form a vacuumclosed space, where the vacuum closed space is configured to encapsulatean OLED layer.
 11. The electronic device according to claim 10, whereinthe electronic device further comprises a second barrier layer, and thesecond barrier layer is stacked on the buffer layer.
 12. The electronicdevice according to claim 11, wherein the second barrier layer surroundsthe first barrier layer and a lateral surface of the buffer layer sothat the OLED layer is surrounded by the first barrier layer and thesecond barrier layer.